Robustness of electrical quality of ion implanted black silicon emitters: Comparison between different ion implantation service providers

Ion implantation provides precise control over the resulting dopant atom density, enabling high-quality optical and electrical performance of nanostructured (black silicon, b-Si) emitters. In this work, we study how sensitive the performance of Al2O3-passivated b-Si emitters is to small variations in the implantation conditions and the equipment used to perform it. We carried out boron emitter implantations for identical nanostructured and planar wafers at four different implantation service providers and with both beam line and parallel beam tool configurations. We then benchmarked the results against the earlier optimised b-Si emitter process. The results show that there are some differences in obtained sheet resistance and emitter saturation current depending on the service provider and the used tool configuration. Finally, there are also some deviations in terms of possible bulk contamination among the different service providers.